1. Field of the Invention
This invention relates to spinklers of the type normally employed in fire extinguishing sprinkler systems.
2. Description of the Prior Art
Sprinklers heretofore known in the art have utilized many variations of struts and levers engaged between the closure caps of the sprinklers and a portion of the frame opposite thereto. See for example U.S. Pat. Nos. 1,231,439 and 1,919,508 wherein fulcrumed levers with inter-engaging fusible elements are disclosed. Fusible elements acting to directly retain closure caps in sprinklers are seen in U.S. Pat. No. 1,945,450 and fusible elements combined with stuts and levers are disclosed in U.S. Pat. Nos. 2,165,477, 3,291,216 and 3,336,984. Sprinklers with horizontally disposed fusible elements arranged to retain strut and lever assemblies engaged against closure caps are seen in U.S. Pat. Nos. 2,502,754, 2,534,065 and 3,625,289.
This invention eliminates several production problems inherent in the manufacture and assembly of the prior art devices in forming the sprinkler so that it can be made and assembled by automatic machinery. The arrangement of the fusible element and its positioning between the apertured arms of the strut of the sprinkler where it effectively retains the lever avoids the alloy cold flow problems heretofore associated with fusible elements in fire extinguishing sprinklers.